This invention relates generally to agricultural combines, and more particularly, to a variably positionable chaff pan for disposition rearwardly of cleaning apparatus of an agricultural combine for conveying chaff from the cleaning apparatus to a chopper and/or spreader, the pan being connected to the cleaning apparatus for oscillation therewith and being positionable and lockable in a range of deployed or operational positions for conveying the chaff, and a range of retracted or stored positions for allowing access to the cleaning apparatus and the chopper and spreader for ease of maintenance, service and inspection thereof, and also for allowing access to and use of a hitch for a header cart or the like located below the pan.
Currently, combines typically include a straw chopper and/or straw spreader for disposing of straw separated from the harvested crop onto the crop field. In addition, some combines have a chaff spreader for spreading the chaff separated from the grain by the cleaning apparatus or system. It is desirable to provide the chaff spreading function, however, it is also desired to eliminate the additional chaff spreader apparatus due to the cost, weight, space, and maintenance requirements thereof. One approach for eliminating the chaff spreader is to route the chaff blown and discharged by the cleaning apparatus into the straw chopper and/or straw spreader so as to be chopped and/or spread over the field thereby. This can be done by mounting the chopper and/or spreader directly behind the chaff discharge end of the cleaning apparatus. However, a shortcoming of this location is that it makes access to the cleaning apparatus for service, maintenance, and inspection difficult, which is undesirable. As an alternative, the chopper and/or spreader can be spaced rearwardly of the cleaning apparatus to provide an access space or gap therebetween for service and the like. However, this space or gap presents a problem as it must be crossed or bridged by the chaff enroute to the chopper and/or spreader. The chaff is typically carried rearwardly by a flow of air blown upwardly through the cleaning apparatus, and to enclose this space to contain the chaff containing air flow and direct it to the chopper and/or spreader, a pan or other enclosure can be used. It is known to mount such pans to the frame or other enclosures of the combine, or to the cleaning apparatus itself, and for the pan or enclosure to be foldable between an operational position and an open position. However, pans or enclosures attached to the combine frame but not to the cleaning apparatus have the disadvantage that they do not provide a continuous path from the cleaning apparatus to the chopper and/or spreader and do not vibrate or oscillate with the cleaning apparatus. Pans attached to the cleaning apparatus will oscillate therewith, but if supported only by the cleaning apparatus can place loads thereon which can degrade the operation of the cleaning system and possibly damage it. Thus, what is sought is a pan for conveying chaff to a chopper and/or spreader located spacedly behind the cleaning apparatus of a combine, that is attachable to the cleaning apparatus for vibration or oscillation therewith, but without unduly loading it, and which is easily and conveniently repositionable or movable for allowing access to the cleaning apparatus and the chopper and/or spreader.
Additionally, some combines have cleaning apparatus which are self-leveling, that is, they pivot or tilt at least sidewardly to compensate for tilting of the combine as it moves across the sides of hills and the like. Thus, it is also sought that a pan for bridging the space between the cleaning apparatus and the chopper and/or spreader be able to pivot or tilt with the cleaning apparatus.
Still further, some combines include a hitch on the rear end thereof beneath the contemplated location for any device for bridging the space between the cleaning apparatus and the chopper and/or spreader, for attaching the tongue of a header cart or the like thereto to allow towing the header cart or the like. It would thus be desirable that a chaff pan be capable of easily accommodating usage of the hitch, without interfering therewith.
What is disclosed is a variably positionable chaff pan for attachment to an oscillating element of a cleaning apparatus or system of an agricultural combine for oscillation therewith for conveying chaff from the oscillating element to a non-oscillating chopper or spreader mounted to a fixed frame of the combine, which chaff pan overcomes many of the shortcomings discussed above and which is sidewardly tiltable with the cleaning apparatus or system, if so capable. The variably positionable chaff pan has a surface for receiving the chaff positionable in at least one operational or first position adjacent to the oscillating element of the cleaning apparatus which can be, for instance, a chaffer, a sieve, a frame or rails supporting the same, or the like, for receiving the chaff therefrom, a pivoting element for connecting the pan to the oscillating element for pivotal movement relative thereto about a generally horizontal axis through a range of positions angularly related to the oscillating element including positions oriented relative thereto for receiving the chaff therefrom, and a linkage arrangement connecting the pan to the fixed frame for supporting the pan in selected ones of the positions within the range of positions while allowing the pan to oscillate with the oscillating element relative to the linkage arrangement, the linkage arrangement including a locking variable length element lockable at lengths within a range of lengths for holding the pan in the positions for receiving the chaff from the oscillating element, respectively, and unlockable such that the length can be varied to allow pivotal movement of the pan to other of the positions within the range of positions.
When the cleaning apparatus is mounted for pivotal movement relative to the frame in a sidewardly direction relative to a direction of oscillation, the linkage arrangement allows sideward movement of the pan relative thereto such that the pan can pivot sidewardly with the cleaning apparatus relative to the linkage arrangement.